Rigid sensor stopper for use in drug delivery devices

ABSTRACT

The present disclosure relates to a stopper adapted for use in a drug delivery device. In one implementation, the stopper includes a rigid casing having a shape adapted to fit within a barrel of the drug delivery device; electronics disposed and sealed within the rigid casing; and an elastomeric seal disposed around at least a dispensing end of the rigid casing and a side of the rigid casing. The electronics include a power source and at least one of a transducer or a sensor coupled to the power source. The elastomeric seal comprises a single continuous material.

RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.Nos. 15/862,375, filed Jan. 4, 2018, which claims priority toprovisional application 62/443,493, filed Jan. 6, 2017, the contents ofwhich are both incorporated by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates generally to the field of drug deliverydevices. More specifically, and without limitation, this disclosurerelates to a rigid sensor stopper adapted for use in a drug deliverydevice. The stopper may be used in various drug delivery devices, forexample, a syringe, infusion pump, auto injector, or an injection pen.

BACKGROUND

Drug delivery systems, such as syringes and injection pens, generallyinclude stoppers, which create a seal within the cartridge or barrel andallow for the drug to be administered when the displacement mechanism(plunger) is depressed. Traditional stoppers are typically fabricatedwith an elastomeric rubber material. Elastomeric materials may not beoptimal for a drug delivery device with a sensor incorporated into thedelivery device and/or drug cartridge because such materials attenuatethe measurement signal.

SUMMARY

In view of the foregoing, embodiments of the present disclosure providea rigid sensor stopper incorporating elastomeric elements. In accordancewith some embodiments, a molded assembly or rigid casing is provided forthe sensor and other electronics. Due to its rigidity, the assembly orcasing reduces attenuation of the measurement signal while remainingcompliant with the drug delivery device. In addition, the elastomericelements can seal the drug cartridge while not interfering with thedisplacement mechanism.

According to an exemplary embodiment of the present disclosure, a rigidsensor stopper is described. The device may include a transducer, abattery, a rigid molding, and at least one seal. The molding may beformed by overmolding surrounding the transducer (or other sensorelements such as optical, magnetic, and capacitive sensors) and thebattery, or insert molding surrounding the transducer and the battery.In one embodiment, the at least one seal may be elastomeric.

According to a yet further exemplary embodiment of the presentdisclosure, a rigid sensor stopper for use in a drug delivery device isdescribed. The device may include a transducer, a battery, a rigidcasing, and at least one seal. The casing may be formed by injectionmolding, machining, or forged casing. Moreover, the transducer and thebattery may be inserted prior to the sealing of the rigid casing, andthe at least one seal may be elastomeric. In one embodiment, the rigidcasing could also be installed into a cartridge and filled prior to theinsertion of electronics.

Additional objects and advantages of the present disclosure will be setforth in part in the following detailed description, and in part will beobvious from the description, or may be learned by practice of thepresent disclosure. The objects and advantages of the present disclosurewill be realized and attained by means of the elements and combinationsparticularly pointed out in the appended claims.

It is to be understood that the foregoing general description and thefollowing detailed description are exemplary and explanatory only, andare not restrictive of the disclosed embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which comprise a part of this specification,illustrate several embodiments and, together with the description, serveto explain the disclosed principles. In the drawings:

FIG. 1 is a cross-sectional schematic representation of an exemplaryrigid sensor stopper, according to embodiments of the presentdisclosure.

FIG. 2A is a cross-sectional schematic representation of anotherexemplary rigid sensor stopper, according to embodiments of the presentdisclosure.

FIG. 2B is a front view of the exemplary rigid sensor stopper of FIG.2A, according to embodiments of the present disclosure.

FIG. 3 is a cross-sectional schematic representation of anotherexemplary rigid sensor stopper, according to embodiments of the presentdisclosure.

FIG. 4 is a cross-sectional schematic representation of anotherexemplary rigid sensor stopper, according to embodiments of the presentdisclosure.

FIG. 5 is a cross-sectional schematic representation of anotherexemplary rigid sensor stopper, according to embodiments of the presentdisclosure.

FIG. 6 illustrates an application of the disclosed rigid sensor stopperin a syringe.

FIG. 7 illustrates a sensor stopper with a thermal protection barrier,in accordance with embodiments of the present disclosure.

FIG. 8 depicts a graph showing how the latent heat of fusion orvaporization can be used to control the temperature of electronics, inaccordance an embodiment of the present disclosure.

FIGS. 9A and 9B depict two examples of wearable devices that may utilizea phase-change-material-surrounded power source, in accordance withemboidments of the present disclosure.

DETAILED DESCRIPTION

The disclosed embodiments relate to a rigid sensor stopper adapted foruse in a drug delivery device, as well as aphase-change-material-protected power source. Advantageously, theexemplary embodiments may reduce attenuation of the measurement signalfrom the sensor while remaining compliant with the drug delivery device.Applications consistent with the present disclosure encompass a syringe,an injection pen, other drug delivery devices, and wearable electronics.

According to an aspect of the present disclosure, a rigid sensor stopperis provided. The stopper may include one or more transducers to detectthe position of the stopper in a cartridge or syringe of a drug deliverydevice (e.g., by sending and receiving ultrasonic signals). The positionof the stopper may be used to calculate a volume of fluid dispensed fromthe cartridge. In some embodiments, the one or more transducers mayinclude an ultrasonic transducer. For example, the one or moretransducers may include a PZT transducer. In other embodiments, othersensors may be included such as an acoustic transceiver, a photodiode,an encoder, a hall effect sensor, etc.

According to a further aspect of the present disclosure, the stopper mayinclude one or more power sources. In some embodiments, the one or morepower sources may comprise a DC power source and include a battery, acapacitor, etc. In other embodiments, the one or more power sources maycomprise an AC power source. In some embodiments, the stopper may bepowered by an external power source through an inductive, RF connection,or the like.

According to a further aspect of the present disclosure, the stopper mayinclude one or more additional electronic elements. By way of example,the one or more electronic elements may include a microcontroller, anamplifier, an analog-to-digital converter, etc.

According to a further aspect of the present disclosure, the stopper mayinclude one or more telemeters or transmitters. By way of example, theone or more telemeters/transmitters may include a radio transmitter, anantenna, etc.

Consistent with embodiments of the present disclosure, the stopper mayinclude a rigid molding. In certain aspects, the molding may be formedfrom overmolding surrounding the sensor, the transducer, the powersource, etc. In other aspects, the molding may be formed from insertmolding surrounding the transducer, the power source, etc.

In other embodiments, the stopper may include a sealed rigid casing. Thetransducer, the power source, etc. may be inserted into the casing priorto sealing it. For example, the casing may be sealed using an adhesive,resistance welding, ultrasonic welding, friction welding, laser welding,Interference fit, snap features, additional fastening components, etc.In certain aspects, the casing may be formed from injection molding. Inother aspects, the casing may be formed from machining. In still otheraspects, the casing may be formed from forged casing.

Consistent with other aspects of the present disclosure, the casing maycomprise glass. The casing may be hermetically sealed using flamesealing. In other aspects, the casing may include a cap. The cap mayseal the casing after the transducer, the power source, etc., areinserted therein.

In some embodiments, the casing may include potting and/or backfill.Advantageously, this may remove dead space within the casing and securethe transducer, the power source, etc. In some embodiments, the casingmay include a getter. Advantageously, this may absorb moisture withinthe casing that could damage the transducer, the power source, etc. Insome embodiments, the casing and the potting may include material whoseacoustic resonance matches the frequency of the transducer, for example,a soundboard. Preferably, such material is rigid in order to function asan effective soundboard. Advantageously, this may improve the range ofthe transducer. In some embodiments, the casing may be optically clearfor optical sensors (for light transmission), or magneticallytransparent for hall sensors, or insulative.

Consistent with embodiments of the present disclosure, the stopper mayinclude at least one seal. The at least one seal may be elastomeric. Insome embodiments, the at least one seal may cover the entirety of thestopper. For example, the at least one seal may be integrated with themolding or casing and may be formed from overmolding or insert molding.In other embodiments, the at least one seal may comprise at least twoo-rings. For example, the at least two o-rings may be integrated withthe molding or casing and may be formed from overmolding or insertmolding. Alternatively, the at least two o-rings may be separated fromthe molding or casing and may sit within glands included on the moldingor casing.

FIG. 1 is a cross-sectional schematic representation of exemplary rigidsensor stopper 100. Stopper 100 may include transducer 101, power source103, and sensor 105. Transducer 101, power source 103, and sensor 105may be connected via one or more electrical connections. Stopper 100 mayfurther include other electronic components, e.g., a microcontroller, anamplifier, an analog-to-digital converter, etc., operably connected totransducer 101, power source 103, and sensor 105. Stopper 100 may alsoinclude one or more telemeters, e.g., a radio transmitter, an antenna,etc., operably connected to transducer 101, power source 103, and sensor105.

In some embodiments, transducer 101 may include an ultrasonictransducer. For example, transducer 101 may include a PZT transducer. Insome embodiments, power source 103 may comprise a DC power source andinclude a battery, a capacitor, etc. In other embodiments, power source103 may comprise an AC power source. In some embodiments, sensor 105 mayinclude, for example, an acoustic transceiver, a photodiode, an encoder,a hall effect sensor, etc.

As depicted in FIG. 1, stopper 100 may include rigid molding 107. Forexample, rigid molding 107 may be formed from overmolding and maysurround transducer 101, power source 103, sensor 105, and any otherelectronics components and telemeters. In other embodiments, rigidmolding 107 may be formed from insert molding and may surroundtransducer 101, power source 103, sensor 105, and any other electronicscomponents and telemeters.

Rigid molding 107, transducer 101, power source 103, sensor 105, and anyother electronics components and telemeters may comprise sensor cone109. Sensor cone 109 may comprise a cone, cylinder, or other conical oroblong shape. FIG. 1 therefore depicts a cross-sectional plane of sensorcone 109.

As depicted in FIG. 1, stopper 100 may further include one or moreelastomeric seals, e.g., o-rings 111 and 113. For example, o-rings 111and 113 may sit within glands, e.g., glands 115 and 117, that may beincluded on rigid molding 107. Here gland recesses are trapezoidal, butin other embodiments gland recesses may be rectangular, semicircular, orthe like.

In stopper 100, sensor 105 may activate due to an environmental change,for example, if the pressure on the stopper increases. In sucharrangements, sensor 105 may use power source 103 to supply power totransducer 101. Power source 103 may drive transducer 101 at a resonancefrequency in order to emit an ultrasonic signal. Transducer 101 emitsultrasonic waves along the length of a cartridge or syringe holding afluid (e.g., insulin), the signals are reflected back towards transducer101 from a dispensing end of the cartridge, and then the ultrasonicsignals are received by transducer 101 (or other sensor/transducer). Thetime between emission and receipt of the ultrasonic signals may be usedto calculate a time of flight. The time of flight data, or other datagenerated by transducer 101, may be sent (e.g., by telemetry) to adetector, (for example, a smart phone, a keychain, or other device todisplay the data to a user) after the signal from transducer 101 isprocessed (e.g., the volume of fluid in the injection device iscalculated with a controller or processor).

FIG. 2A is a cross-sectional schematic representation of exemplary rigidsensor stopper 200. Stopper 200 may include a plurality of electronics201. For example, the plurality of electronics may include a transducer,a power source, a sensor, a microcontroller, an amplifier, ananalog-to-digital converter, a radio transmitter, an antenna, etc., orany combination thereof. The plurality of electronics 201 may beoperably connected to each other.

As depicted in FIG. 2A, stopper 200 may include rigid molding 203. Forexample, rigid molding 203 may be formed from overmolding and maysurround the plurality of electronics 201. In other embodiments, rigidmolding 203 may be formed from insert molding and may surround theplurality of electronics 201.

As depicted in FIG. 2A, stopper 200 may further include one or moreelastomeric seals, e.g., seals 205 and 207. In some embodiments, seals205 and 207 may be formed from overmolding and may be integrated withrigid molding 203. In other embodiments, seals 205 and 207 may be formedfrom insert molding and may be integrated with rigid molding 203. Seals205 and 207 may also be formed separately and bonded.

Rigid molding 203, the plurality of electronics 201, and seals 205 and207 may comprise sensor cone 209. Sensor cone 209 may comprise a cone,cylinder, or other conical or oblong shape. FIG. 2A therefore depicts across-sectional plane of sensor cone 209.

In stopper 200, a sensor included in the plurality of electronics 201may activate due to an environmental change, for example, if thepressure on the stopper increases, temperature changes, ambient lightchanges, electrical conductivity of solution changes, capacitance orresistance changes, or the stopper is exposed to an RF field (e.g.,RFID, NFC, etc.). In such arrangements, the sensor may use a powersource included in the plurality of electronics 201 to supply power to atransducer included in the plurality of electronics 201. The powersource may drive a transmitter or telemeter (e.g., RF, Bluetooth or thelike) in order to transmit a data signal to an external device. The datasignal from the transmitter may be received by a detector included in,for example, a smart phone, a keychain, or other device adapted toreceive data signals from the transmitter and display data to the user(e.g., on a screen).

FIG. 2B is a front view of exemplary rigid sensor stopper 200 of FIG.2A. FIG. 2B shows the overall shape of sensor cone 209 of stopper 200.

FIG. 3 is a cross-sectional schematic representation of exemplary rigidsensor stopper 300. Stopper 300 may include a plurality of electronics301. For example, the plurality of electronics may include a transducer,a power source, a sensor, a microcontroller, an amplifier, ananalog-to-digital converter, a radio transmitter, an antenna, etc., orany combination thereof. The plurality of electronics 301 may beoperably connected to each other.

As depicted in FIG. 3, stopper 300 may include rigid molding 303. Forexample, rigid molding 303 may be formed from overmolding and maysurround the plurality of electronics 301. In other embodiments, rigidmolding 303 may be formed from insert molding and may surround theplurality of electronics 301.

As depicted in FIG. 3, stopper 300 may further include an elastomericseal, e.g., seal 305. In some embodiments, seal 305 may be formed fromovermolding and may surround rigid molding 303. In other embodiments,seal 305 may be formed from insert molding and may surround rigidmolding 303. In the depicted embodiment, seal 305 and the ridges, whichare substantially trapezoidal, are one continuous piece of material(rather than using o-rings).

Rigid molding 303, the plurality of electronics 301, and seal 305 maycomprise sensor cone 307. Sensor cone 307 may comprise a cone, cylinder,or other conical or oblong shape. FIG. 3 therefore depicts across-sectional plane of sensor cone 307.

In stopper 300, a sensor included in the plurality of electronics 301may activate due to an environmental change, for example, if thepressure on the stopper increases. In such arrangements, the sensor mayuse a power source included in the plurality of electronics 301 tosupply power to a transducer included in the plurality of electronics301. The power source may drive the transducer at a resonance frequencyin order to emit an ultrasonic signal. A data signal may be sent from atransmitter (also coupled to the power source) and may be received by adetector, for example, a smart phone, a keychain, or other deviceadapted to receive data signals and display data to the user.

FIG. 4 is a cross-sectional schematic representation of exemplary rigidsensor stopper 400. Stopper 400 may include a plurality of electronics401. For example, the plurality of electronics may include a transducer,a power source, a sensor, a microcontroller, an amplifier, ananalog-to-digital converter, a radio transmitter, an antenna, etc., orany combination thereof. The plurality of electronics 401 may beoperably connected to each other.

As depicted in FIG. 4, stopper 400 may include rigid casing 403. Forexample, rigid casing 403 may surround the plurality of electronics 401.In some embodiments, rigid casing 403 may be formed from injectionmolding. In other embodiments, rigid casing 403 may be formed frommachining. In still other embodiments, rigid casing 403 may be formedfrom forged casing.

Stopper 400 may further include potting and/or backfill (see infradiscussion of phase change material and FIG. 7) within rigid casing 403.Advantageously, this may remove dead space within casing 403 and securethe plurality of electronics 401. Stopper 400 may further include agetter (e.g., a substance used to remove residual gas/liquid) withinrigid casing 403. Advantageously, this may absorb moisture within casing403 that could damage the plurality of electronics 401. Stopper 400 mayfurther include soundboard (e.g., a thin sheet of material to improvewave production) within rigid casing 403. Advantageously, this mayimprove the range of a transducer included in the plurality ofelectronics 401.

Rigid casing 403 may be sealed using cap 405. For example, cap 405 mayseal rigid casing 403 after the plurality of electronics 401 have beeninserted therein. In some embodiments, an adhesive may attach cap 405 torigid casing 403. In other embodiments, cap 405 may be welded onto rigidcasing 403. In some embodiments, cap 405 may be secured by aninterference fit, or include snap (e.g., snaps on the cap or on therigid casing) fasteners, or may be secured by additional fasteners.

As depicted in FIG. 4, stopper 400 may further include an elastomericseal, e.g., seal 407. In some embodiments, seal 407 may be formed fromovermolding and may surround rigid casing 403. In other embodiments,seal 407 may be formed from insert molding and may surround rigid casing403.

Rigid casing 403, the plurality of electronics 401, and seal 407 maycomprise sensor cone 409. Sensor cone 409 may comprise a cone, cylinder,or other conical or oblong shape. FIG. 4 therefore depicts across-sectional plane of sensor cone 409.

In stopper 400, a sensor included in the plurality of electronics 401may activate due to an environmental change, for example, if thepressure on the stopper increases. In such arrangements, the sensor mayuse a power source included in the plurality of electronics 401 tosupply power to a transducer included in the plurality of electronics401. The power source may drive the transducer at a resonance frequencyin order to emit an ultrasonic signal. A transmitter may send a datasignal that is received by a detector, for example, a smart phone, akeychain, or other device adapted to receive signals from thetransmitter and display data (e.g., the volume of the cartridge orsyringe) to the user.

FIG. 5 is a cross-sectional schematic representation of exemplary rigidsensor stopper 500. Stopper 500 may include a plurality of electronics501. For example, the plurality of electronics may include a transducer,a power source, a sensor, a microcontroller, an amplifier, ananalog-to-digital converter, a radio transmitter, an antenna, etc., orany combination thereof. The plurality of electronics 501 may beoperably connected to each other.

As depicted in FIG. 5, stopper 500 may include rigid casing 503. Forexample, rigid casing 503 may surround the plurality of electronics 501.In certain aspects, rigid casing 503 may include glass. In someembodiments, rigid casing 503 may be sealed with flame sealing after theplurality of electronics 501 have been inserted therein. In otherembodiments, rigid casing 503 may be sealed with laser sealing after theplurality of electronics 501 have been inserted therein.

Stopper 500 may further include potting and/or backfill within rigidcasing 503. Advantageously, this may remove dead space within casing 503and secure the plurality of electronics 501. Stopper 500 may furtherinclude a getter within rigid casing 503. Advantageously, this mayabsorb moisture within casing 503 that could damage the plurality ofelectronics 501. Stopper 500 may further include soundboard within rigidcasing 503. Advantageously, this may improve the range of thetransducer.

Rigid casing 503 and the plurality of electronics 501 may comprisesensor cone 505. Sensor cone 505 may comprise a cone, cylinder, or otherconical or oblong shape. FIG. 5 therefore depicts a cross-sectionalplane of sensor cone 505.

As depicted in FIG. 5, stopper 500 may further include one or moreelastomeric seals, e.g., o-rings 507 and 509. For example, o-rings 507and 509 may sit within glands (e.g., recesses) that may be included onrigid casing 503.

In stopper 500, a sensor included in the plurality of electronics 501may activate due to an environmental change, for example, if thepressure on the stopper increases. In such arrangements, the sensor mayuse a power source included in the plurality of electronics 501 tosupply power to a transducer included in the plurality of electronics501. The power source may drive the transducer at a resonance frequencyto emit the ultrasonic signals. A transmitter may send data signals to adetector, for example, a smart phone, a keychain, or other deviceadapted to receive signals from the transmitter and display data to theuser (e.g., in the form of a graph, table, or the like).

FIG. 6 is a schematic representation of an application of a rigid sensorstopper (e.g., 100, 200, 300, 400, 500, or any combination thereof) in asyringe 600. In the example of FIG. 6, syringe 600 may include a barrel601, a tip 603, a needle 605, and a dispensing mechanism 607. Theexample of FIG. 6 may further include a rigid sensor stopper 609.Stopper 609 may comprise stopper 100, 200, 300, 400, 500, or anycombination thereof, consistent with the present disclosure.

In syringe 600, depressing dispensing mechanism 607 causes medicinecontained within barrel 601 to move towards tip 603 and through needle605. One or more seals, e.g., seals 611 and 613, included in rigidsensor stopper 609 may form a seal with barrel 601 such that themedicine contained within barrel 601 is forced through the dispensingend and needle 605. A sensor included in rigid sensor stopper 609 mayactivate when dispensing mechanism 607 is depressed because, forexample, stopper 609 will undergo an increase in pressure. The sensormay use a power source included in rigid sensor stopper 609 to supplypower to a transducer included in rigid sensor stopper 609. The powersource may drive the transducer at a resonance frequency in order toemit an ultrasonic signal. A transmitter may emit a data signal which isreceived by a detector, for example, a smart phone, a keychain, or otherdevice adapted to receive data signals from the transmitter and displaydata to the user.

In syringe 600, further depressing dispensing mechanism 607 causes rigidsensor stopper 609 to enter tip 603. A sensor included in rigid sensorstopper 609 may activate when entering tip 603 because, for example,stopper 609 will undergo an decrease in pressure.

FIG. 7 shows a sensor stopper 700 with a thermal protection barrier 751.Sensor stopper 700 includes transducer 701, power source 703 (e.g., abattery, capacitor), microcontroller 721 (e.g., processor), molding 707,can/housing 753, and phase change material 751. It is appreciated thatthe components depicted here are all compatible with the previouslydescribed stoppers (e.g., 100, 200, 300, 400, 500, or any combinationthereof).

Aqueous based batteries, such as silver oxide, alkaline zinc, etc. maysuffer from damage when exposed to high temperatures due to high cellinternal pressure (boiling of electrolyte), faster corrosionreaction/side reaction at high temperatures, compromised sealing due tosoftening of the sealing element, etc. Often, medical devices integratedwith batteries need to go through a sterilization process in whichbatteries can be exposed to 125° C. for −30 mins. Here, phase changematerial 751 is used to prevent the negative effects of high temperatureexposure.

In the depicted embodiment, stopper 700 includes transducer 701 which iscoupled to emit ultrasonic signals (e.g., curved lines in the cartridgetraveling away from stopper 700) through a fluid in the drug deliverydevice, along a length of the device, when the stopper is positioned inthe drug delivery device (e.g., the cartridge of an insulin pen or thebody of a syringe). As shown, the ultrasonic signals are reflected backtoward the stopper by a dispensing end of the cartridge (see e.g.,curved lines traveling towards stopper 700). As shown, the dispensingend of stopper 700 is the narrowing, or neck, region of the cartridgewhich provides a flat surface for the ultrasonic signals to be reflectedoff of. Power source 703 is disposed in stopper 700, and coupled totransducer 701 to supply power to transducer 701. Power source 703 isdisposed within phase change material 751 (depicted as parallel linesfilling can 753), and phase-change material 751 has a chemical structureto change phase at a temperature lower than a degradation temperature ofthe battery (e.g., the temperature at which the battery is at least oneof physically damaged, has a permanent reduction in specific energy, orhas a permanent reduction in specific power).

Microcontroller 721 is coupled to transducer 701 and power source 703.Controller 721 includes logic that, when executed by controller 721,causes stopper 700 to perform a variety of operations. For example,controller 721 may calculate a time of flight for the ultrasonicsignals, a position of the plunger head, a volume of the cartridge,instruct the transmitter to send a data signal, or the like. In thedepicted embodiment, both battery 703 and microcontroller 721 are placedin can 753 (e.g., a plastic or metal enclosure) and oriented orthogonalto transducer 701.

In some embodiments, controller 721 may calculate a time of flight forthe ultrasonic signals to travel from transducer 701 and return tostopper 700 (e.g., be received by transducer 701 or another transducerin stopper 700). The time of flight may be used to calculate theposition of stopper 700 in the cartridge. The position of stopper 700may then be used to calculate a volume of fluid, medication, or insulinleft in the cartridge.

As shown, one way to protect the electronics in sensor stopper 700 is tosurround them with, or immerse them in, a material 751 (e.g.,hydrocarbons like wax, or other low molecular weight polymer) thatundergoes a phase change (e.g., solid to liquid, liquid to gas, orchange between different crystal structures) at, or around, thesterilization temperature. This is because when materials change phase,the material's temperature remains constant. The heat supplied during aphase change is called latent heat (e.g., of fusion or vaporization).The energy supplied by the heat is used to change the molecular/atomicorganization of the material rather than cause a temperature increase.When the phase change is completed, further transfer of heat will resultin the temperature increasing. Here, a material may be selected toundergo a phase change at or around the sterilization temperature, toprevent the temperature of the microelectronics, including battery 703,from getting too hot.

In some embodiments, in addition to surrounding battery 703 with a phasechange material, a specially designed high-temperature battery 703(e.g., Li/CF_(x) or Li/SOCl₂) may be employed. Battery 703 may includehigh boiling point solvent and a special sealing design. For example thebattery could be FDK ML614 and have 3.4 mAh, and a max current of 15 uA.Similarly, battery 703 may be a reflowable ML614R which has 2.5 mAh and5 uA discharge current. In a different embodiment, the battery may be alow-cost battery, and phase change material 751 provides adequateprotection for sterilization.

In specific embodiments, electronics may be embedded (e.g., the phasechange material may be in liquid form and poured into can 753 around theelectronics) in phase change material 751 that has a phase changetemperature lower than 150° C., 140° C., 130° C., 120° C., 110° C., or100° C. The overmolded electronics may be loaded into a premolded butylrubber cupped stopper 707 to form stopper 700. During the sterilizationprocess, phase change material 751 will melt but will maintain its phasechange temperature for some time without heating up battery 703.Depending stages of the sterilization process, phase change material 751can be a mixture of phase change materials with different meltingtemperatures to manage the heat from the sterilization process. Putanother way, phase change material 751 may include a plurality ofmaterials, and each material in the plurality of materials has adifferent phase transition temperature.

FIG. 8 depicts a graph showing how the latent heat of fusion orvaporization can be used to control the temperature of power source andother sensitive electronics. As shown, at the latent heat offusion/vaporization, the temperature of the material is constant. Thisprovides protection for the microelectronic devices that may becontained within. One of ordinary skill in the art having the benefit ofthe present disclosure will appreciate that this phase change techniqueto protect electronics during sterilization, may be used with otherdevices (e.g., continuous glucose monitors, wearable insulin deliverysystems, other patch-like health monitoring devices, and evenimplantable medical devices) and not just the stopper described herein.

FIGS. 9A and 9B depict two examples of wearable devices that may utilizethe phase-change-material-surrounded power source discussed above, inaccordance with the teachings of the present disclosure. FIG. 9A depictsa continuous glucose monitor 900A (e.g., an adhesive patch) that mayinclude a controller, glucose sensor (e.g., chemical sensor array),adhesive layer 903, and power source (e.g., battery) surrounded by aphase change material. All of these components may be disposed inhousing 903. In some embodiments, the glucose monitor 900A may double asan insulin delivery system or. Moreover, glucose monitoring patch 900Amay also include other sensors to detect physical attributes such asheart rate, blood pressure, or the like.

Similarly FIG. 9B shows an example pacemaker 900B which may include apower source surrounded by a phase change material as well as otherelectronic components (e.g., microcontroller, electrodes 901, etc.).Like the other embodiments, the phase change material may be disposedaround the power source (and other electronics described herein) soduring sterilization, the power source is not damaged.

The foregoing description has been presented for purposes ofillustration. It is not exhaustive and is not limited to precise formsor embodiments disclosed. Modifications and adaptations of theembodiments will be apparent from consideration of the specification andpractice of the disclosed embodiments. For example, the describedimplementations include hardware, but systems and methods consistentwith the present disclosure can be implemented with hardware andsoftware. In addition, while certain components have been described asbeing coupled to one another, such components may be integrated with oneanother or distributed in any suitable fashion.

Moreover, while illustrative embodiments have been described herein, thescope includes any and all embodiments having equivalent elements,modifications, omissions, combinations (e.g., of aspects across variousembodiments), adaptations and/or alterations based on the presentdisclosure. The elements in the claims are to be interpreted broadlybased on the language employed in the claims and not limited to examplesdescribed in the present specification or during the prosecution of theapplication, which examples are to be construed as nonexclusive.

The features and advantages of the disclosure are apparent from thedetailed specification, and thus, it is intended that the appendedclaims cover all systems and methods falling within the true spirit andscope of the disclosure. As used herein, the indefinite articles “a” and“an” mean “one or more.” Similarly, the use of a plural term does notnecessarily denote a plurality unless it is unambiguous in the givencontext. Words such as “and” or “or” mean “and/or” unless specificallydirected otherwise. Further, since numerous modifications and variationswill readily occur from studying the present disclosure, it is notdesired to limit the disclosure to the exact construction and operationillustrated and described, and accordingly, all suitable modificationsand equivalents may be resorted to, falling within the scope of thedisclosure.

Other embodiments will be apparent from consideration of thespecification and practice of the embodiments disclosed herein. It isintended that the specification and examples be considered as exampleonly, with a true scope and spirit of the disclosed embodiments beingindicated by the following claims.

What is claimed is:
 1. A stopper, comprising: a rigid casing having ashape adapted to fit within a barrel of a drug delivery device;electronics disposed and sealed within the rigid casing, wherein theelectronics include a power source and at least one of a transducer or asensor coupled to the power source; and an elastomeric seal adapted toform a seal with the barrel when the stopper is inserted into the barrelof the drug delivery device, the elastomeric seal disposed around atleast a dispensing end of the rigid casing and a side of the rigidcasing and wherein the elastomeric seal comprises a single continuousmaterial.
 2. The stopper of claim 1, further comprising: a cap disposedover an end of the rigid casing opposite the dispensing end, wherein thecap seals the electronics within the rigid casing.
 3. The stopper ofclaim 2, wherein the cap is secured to the rigid casing via aninterference fit, one or more fasteners, a weld joint, or an adhesive.4. The stopper of claim 1, wherein the elastomeric seal extends aroundand fully encases the rigid casing.
 5. The stopper of claim 4, whereinthe elastomeric seal comprises an overmold.
 6. The stopper of claim 1,wherein the elastomeric seal includes a ridge that encircles the side ofthe rigid casing and is adapted to seal against the barrel of the drugdelivery device when the stopper is inserted into the drug deliverydevice.
 7. The stopper of claim 6, wherein the elastomeric seal includesa pair of ridges including the ridge that encircle the side of the rigidcasing and are adapted to seal against the barrel of the drug deliverydevice when the stopper is inserted into the drug delivery device. 8.The stopper of claim 7, wherein the pair of ridges are part of thesingle continuous material of the elastomeric seal.
 9. The stopper ofclaim 1, wherein the elastomeric seal comprises a coating of the singlecontinuous material on outer surfaces of the rigid casing.
 10. Thestopper of claim 1, further comprising: a phase-change material disposedwithin the rigid casing, the phase-change material having a chemicalstructure that changes phase at a temperature lower than a degradationtemperature of the power source.
 11. The stopper of claim 10, whereinthe degradation temperature is a temperature at which the power sourceis at least one of physically damaged, has a permanent reduction inspecific energy, or has a permanent reduction in specific power.
 12. Thestopper of claim 10, wherein the chemical structure of the phase-changematerial undergoes a solid-to-liquid transition or a solid-to-gastransition at the temperature lower than the degradation temperature ofthe power source.
 13. The stopper of claim 10, wherein the phase changematerial is disposed in physical contact with the power source.
 14. Thestopper of claim 10, wherein the phase change material surrounds atleast the power source.
 15. The stopper of claim 10, wherein thephase-change material includes at least one of a polymer or ahydrocarbon.
 16. The stopper of claim 10, wherein the phase changematerial includes a plurality of materials, and wherein each material inthe plurality of materials has a different phase transition temperature.17. The stopper of claim 1, wherein the power source includes at leastone of a battery including silver oxide, alkaline zinc, Li, CF_(x), orSOCl₂.
 18. The stopper of claim 1, wherein the electronics furthercomprise at least one of: a microcontroller, an amplifier, ananalog-to-digital converter, a radio transmitter, or an antenna.
 19. Thestopper of claim 1, wherein the electronics further include a controllercoupled to the transducer and the power source, wherein the controllerincludes logic that when executed by the controller causes the stopperto perform operations including: calculating a time of flight forultrasonic signals to travel from the transducer, reflect off of adispensing end of the barrel and return to the stopper.
 20. The stopperof claim 1, wherein the rigid casing comprises an overmold of theelectronics and the electronics are embedded within rigid casing.